Furniture construction



Oct. 1, 1963 w. G. ARNDT 3,105,719

FURNITURE CONSTRUCTION Filed June 15, 1960 4 Sheets-Sheet 2 INVENTOR: WALTER G. ARNDT ATT'YS Oct. 1, 1963 w. G. ARNDT 3,105,719

FURNITURE CONSTRUCTION Filed June 15, 1960 4 Sheets-Sheet 3 30 INVENTOR:

WALTER G. ARNDT M WcM/ww ATT'YS Oct. 1, 1963 w. G. ARNDT FURNITURE CONSTRUCTION 4 Sheets-Sheet 4 Filed June 15; 1960 //f///vi// INVENTOR. WALTER e. ARNDT MAMMiM ATT' YS United States Patent 3,105,719 FURNITURE CONSTRUCTIGN Walter G. Arndt, Chicago, Ill., assignor to Arlington Seating Company, Arlington Heights, EL, :1 corporation of Illinois Filed June 15, 1960, Ser. No. 36,413 8 Claims. (Cl. 297l70) This invention relates to furniture construction and, more particularly, to furniture construction which is particularly well adapted for use in the construction of chairs and combination desks and chairs, and the like.

A primary object of the present invention is to provide a novel, practical furniture construction.

Another object is to enable articles of furniture to be supported in a novel and expeditious manner.

Another object of the present invention is to provide a novel chair wherein the seat portion thereof may be supported in a novel and expeditious manner.

A further object is to enable the back-rest of a chair to be supported in a novel and expeditious manner.

Another object of the present invention is to provide a novel chair of the so-called straight-back type which is particularly well adapted for use in schoolrooms and the like.

Yet another object of the present invention is to afford a novel chair of the aforementioned type wherein the supporting legs therefor and a seat back may be attached to the seat panel thereof by novel structure which includes a unitary supporting panel secured to the seat member and supportingly engaged with supporting legs and the seat back in a novel and expeditious manner.

Another object of the present invention is to afford a novel chair of the aforementioned type wherein the parts of the supporting panel are constituted and arranged in a novel and expeditious manner.

An object ancillary to the foregoing is to enable such a supporting panel to be afforded in the form of a single unitary stamping, or the like.

Another object of the present invention is to provide a novel supporting structure, which is equally well adapted for use in a straight-back chair, by itself, or in a combination chair and desk unit, and the like.

A further object of the present invention is to enable a novel combination desk and chair unit to be provided wherein the desk unit may be connected to the seat portion of the chair in a novel and expeditious manner.

Yet another object of the present invention is to afford a novel combination chair and desk unit of the aforementioned type wherein the parts thereof are constituted and arranged in a novel and expeditious manner whereby the desk portion of the unit affords a practical partial support for the chair portion, and the chair portion likewise affords a practical partial support for the desk portion.

Another object of the present invention is to enable a novel combination desk and chair unit of the aforementioned type to be afforded wherein the desk portion and chair portion of the unit may be folded together for shipment, storage, and the like, in a novel and expeditious manner.

Another object of the present invention is to enable novel furniture to be afforded which is practical and efiicient in construction, and which may be readily and economically produced commercially.

Other and further objects of the present invention will be apparent from the following description and claims and are illustrated in the accompanying drawings which, by way of illustration, show preferred embodiments of the present invention and the principles thereof and what I now consider to be the best mode in which I have contemplated applying these principles. Other embodiments of the invention embodying the same or equivalent prinice ciples may be used and structural changes may be made as desired by those skilled in the art without departing from the present invention and the purview of the appended claims.

In the drawings:

- FIG. 1 is a front perspective view of a chair embodying the principles of the present invention;

FIG. 2 is a fragmentary rear elevational view of the upper portion of the back-rest of the chair shown in FIG. 1;

FIG. 3 is a bottom plan view of the chairshown in FIG. 1;

FIG. 4 is a bottom perspective view of a portion of the chair shown in FIG. 3;

FIG. 5 is a detail sectional view taken substantially along the line 55 in FIG. 4;

FIG. 6 is a detail sectional view taken substantially along the line 66 in FIG. 4;

FIG. 7 is a detail sectional view taken along the line 7--'7 in FIG. 4;

FIG. 8 is a front perspective view of a modified form of the present invention;

FIG. 9 is a fragmentary bottom plan view of the form of the invention shown in FIG. 8;

FIG. 10 is a fragmentary, detailed sectional view taken substantially along the line 10-10 in FIG. 9;

FIG. 11 is a bottom perspective view of the form of the invention shown in FIG. 8, but with the parts thereof disposed in different positions, and with certain parts removed so as to show underlying parts;

FIG. 12 is a fragmentary, exploded, perspective view of a portion of the structure shown in FIG. 11;

FIG. 13 is a detail sectional view taken substantially along the line 13-13 in FIG. 11; and

FIG. 14 is a detail sectional view taken substantially along the line 14-14 in FIG. 11.

A chair I, embodying the principles of the present invention, is shown in FIGS. 1 to 7, inclusive, of the drawings to illustrate the preferred embodiment of the present invention.

The chair 1 includes, in general, a seat 2 supported in elevated position on two rear legs 3 and 4 and two front substantially legs 5 and 6, with a back-rest 7 projecting upwardlyabove the seat 2.

The seat 2 is shown in the drawings as constituting merely a single panel construction, which may be made of any suitable material such as, for example, wood, plastic, or the like. However, it will be appreciated by those skilled in the art that this is merely by way of illustration, and not by way of limitation, and that the seat 2 may have any suitable, desired construction such as a padded seat construction, or the like, without departing from the purview of the present invention.

The seat 2 shown in the drawings is disposed in substantially horizontally extending position, and includes a front edge portion 8, a rear edge portion 9 and two oppositely disposed side edge portions 10 and 11. A panel member'or supporting panel 12, which may be made of any suitable material such as, for example, sheet steel, is mounted on the lower face 13 of the seat r2 and is secured in juxtaposition thereto by suitable means such as rivets 14 extending through the seat 2 and spaced peripheral edge portions of the panel member 13, such as the corners thereof.

The panelmember '12 includes a front edge '15, a rear edge "16 and two oppositely disposed side edges 17 and 18. The edges 15-18 of the panel member 17. are disposed inwardly of, and in substantially parallel relation to, the edges 8*11, respectively, of the seat 2, FIG. 3.

Four upwardly opening elongated recesses or .concavities 19,20, 21 and 22 are formed in the rear edge portion of the panel member %12 in spaced parallel relation to each other. The concavities .19-22 extend from the rear edge 16 of the panel member 12 forwardly toward the front edge 15 and terminate in rearwardly spaced relation to the latter. Another upwardly opening elongated concavity 23 is formed in the front edge portion of the panel member 12 and extends thereacross between the edges 17 and \18, forwardly of the concavities 19-22 and in rearwardly spaced substantially parallel relation to the front edge 15, FIG, 3.

With this construction, when the panel member 12 is mounted in operative position on the seat 2, as shown in FIG. 3, elongated chambers 24, 25, 26, 27 and 28 are disposed between, and defined by the lower face 13 of the seat 2 and the portions 19-23, respectively, of the panel member 12, FIGS. 3, 5 and 7. Each of the chambers 24-27 open outwardly, at the rear end thereof, be-

tween the lower face '13 of the seat 2 and the rear edge 16 of the panel member 12, and the chamber 28 opens outwardly at its opposite ends between the lower face 1 3 of the seat 2 and the edges 17 and 18, respectively, of the panel member 12.

The legs 3-6 may be made of any suitable material, such' as, for example, tubular steel, and are substantially L-shaped in construction, each having a short upper portion 29 and a long lower end portion 30, with the portions 29 and '30 of each of the legs 5 and 6 disposed at an obtuse angle to each other, FIGS. 1 and 3. The portion 29 of the legs 3-6 are preferably cylindrical in shape, and are complementary in transverse cross-sectional size to the chambers 24, 27 and 28 so that they may be inserted thereinto and fit therein with a relatively snug, freely slidable fit.

The upper end portions 29 of the rear legs 3 and 4 are disposed in the chambers 24- and 27, respectively, and

project rearwardly therefrom. The lower end portions 30 of the rear legs -3 and 4 extend downwardly and preferably rearwardly and laterally outwardly from the portions 29 thereof, FIGS. 1 and 3.

The upper end portions of the front legs 25 and 26 are disposed in the opposite ends of the chamber 28 and project laterally outwardly from the edges 17 and 18, respectively, of the panel member 12. The lower end portions of the front legs '5 and 6 project downwardly, and preferably forwardly and laterally outwardly from the upper end portions 29 thereof, FIGS. 1 and 3.

The lower end portions 30 of the legs 3-6 shown in the drawings are tapered, gradually reducing in transverse cross section from the top toward the bottom therepanel 32 mounted on an upper end portion of two substantially parallel L-shaped' supporting members 33 and 34, FIG. 1. The supporting members 33 and 34 may be made of any suitable matenial, such as, for example, tubular steel, and the upper end portions 35 and 36 thereof are disposed in forwardlyope'ning concavities 37 and 38, respectively, formed in a mounting plate 39 secured to the rear face 40 of the back-rest panel 32 by suitable means such as rivets 41. The lower end portions 42 and 43 of the supporting members 33 and'34, respectively, are disposed at substantially right, angles to the upper end portions 35 and 36-and are mounted in the chambersQS and 26 formed between the bottom face 13 of the seat 2 and the portions20' and 21 of'the panel member 12, respectively, FIG. 3. The bottomend portions 42 and 43 of the back-rest of the supporting members 33 and 34 project rearwardly from the rear edge 16 of the panel member 12 behind the rear edge 9 of the seat 2, and the upper end portions 35 and 36 project upwardly therefrom to thereby support the back-rest panel 32 in upwardly spaced relation to the seat 2, MG. 1.

The back-rest panel 32 may be made of any suitable material such as, for example, wood, plastic, or the like,

, by stamping the same from sheet steel.

and the clamping plate 36 may be made of any suitable material such as, for example, sheet steel.

In constructing and assembling the chair 1, the seat 2 and the back-rest panel 32 may be manufactured as separate units and afforded any suitable finish such as, for

example, a varnished finish. The panel member 1 2 and V the clamping plate 39 may also be manufactured as s'cp arate units in any suitable manner such as, for example, The upper end portions 35 and 36 of the back-rest supporting members 33 and 34 may then be mounted-in proper position in the concavities 3'7 and 38 in the clamping plate 39 and secured in such position by suitable means such as, for example, spot welding. The upper end portions 29 of the legs '3 and 4 may be mounted in proper position in the concavities 19 and 22, respectively, in the panel member 12,

and the upper end portions 29 of the front legs 5 and 6: i

tions '42 and 43 of the back-rest supporting members i 34 and 35 may be mounted in proper position in the,

concavities 20 and 21 of the panel member 12 and-se cured thereto by suitable means such as, for example,

spot welding.

Thereafter, the clamping plate 39 and the panel member 12 may be given any suitable finish such as, for example, one or more coats of enamel, and the plate 39 and the panel member 12 may then be riveted to thebackrest panel 32 and the, seat panel 2, respectively. Thus, it will be seen that the chair 1 may be quickly and easily assembled, and the various parts thereof may be readily and economically produced commercially.

In addition to the concavities 19-23, a plurality of reinforcing ribs 44, 45, 46, 47, 48 and 49, in the form of the drawings, the ribs 44 and 45 constitute forward ex tensions of the concavities 20 and 21 and extend across the concavity 23 in substantially perpendicular relation to the latter; the ribs 48 and 49 constitute forward exten sions of the concavities 19 and 22, respectively; the rib 46 interconnects the front end portions of the ribs 48 and 49 and extends across the rear end portions of the ribs 44 and 45 in rearwardly spaced, parallel relation to the concavity 23; and the rib 47 extends across the rearend portions of the concavities 19-22 in forwardly spaced, sub stantially parallel relation to the rear edge 16 of the panel member 12, FIGS. 3 and 4. 'With the panel member 12 constructed in this manner, a strong, practical and efficient supporting panel is afforded, which may be readily and economically produced commercially.

In FIGS. 8 to 14, inclusive, of the drawings a modified form of the present invention is shown which embodiesa chair having the same construction as the chair 1 shown in FIGS. 1 to 7, inclusive, except that the front legs 5 and f 6 thereof have been eliminated and a desk unit 50 has been substituted therefor to thereby afford a combinationchair and desk unit 51. The parts of the combination deskand chair unit 51 shown in FIGS. 8-14, which are the same as the parts embodied in the chair 1 shown in FIGS. 1-7, inclusive, are indicated by the same reference numeralsas the partsshown in FIGS. l-7. 7

Thus, it will be seen that the combination deslcand chair unit 51 includes a seat 2 mounted on the upper end tion of the seat 2. A panel member 12, which is identical in construction to the panel member 12 embodied in the chair 1, is mounted on the lower face 13 of the seat 2 of the combination desk and chair unit 51 in the same man:

ner that the panel member 12 is mounted on the seat 2 of the chair 1 shown in FIGS. 1-7, inclusive. Also, the legs 3 and 4, and the back-rest 7, are secured to the panel member 12 and, therefore, to the seat 2 of the combination desk and chair unit 51 in the same manner as the correspondingparts are secured to the panel member 12 and the seat 2 of the chair 1, as previously described.

The desk unit 50 which is attached to the seat 2 of the combination desk and chair unit 51 includes an elongated rod 52 mounted in the chamber 28 defined by the lower face 13 of the seat 2 and the downwardly-concave portion 23 of the panel member 12. One end portion 52a of the rod 52 extends outwardly from the edge 17 of the panel member 12, the other end 52b of the rod 52 terminates in uniplanar relation to the edge 18 of the panel member 12 and is closed by a cap member 520 mounted therein, FIGS. 9, l0 and 12. The rod 52 is secured in position in the concavity 23 by suitable means such as, for example, spot welding, and is of such cross-sectional size that, when the panel member 12 is secured to the lower face 13 of the seat 2, the rod 52 is disposed in spaced relation to face 13, for reasons which will be discussed in greater detail presently.

The desk unit 50 also includes a substantially rectangular-shaped body portion 53 having a fiat, uniplanar, panel or desk top 54 mounted on the top thereof in substantially horizontally extending position. The bottom 55 of the desk body 53 is substantially flat and an elongated supporting member 56, FIGS. 8, 9 and 11, is attached thereto for assisting in supporting the desk body 53, as will be discussed in greater detail presently.

The supporting member 56 may be made of any suitable material such as, for example, steel tubing and has a substantially U-shaped uniplanar head portion 57 at one end thereof. The head portion 57 includes two spaced, substantially parallel legs 53 and 59 interconnected by an elongated intermediate leg 60, FIGS. 8 and 11. In the combination desk and chair unit 51, the head portion 57 is disposed in underlying relation to the desk body 53 in juxtaposition to the bottom 55 thereof, with the legs 58 and 59 extending along opposite lateral sides of the bottom 55, in inwardly spaced, closely adjacent, parallel relation thereto, and the intermediate leg 60 disposed in closely adjacent, rearwardly spaced, parallel relation to the front edge of the bottom 55 of the desk body 53, FIG. 8. The head 57 of the supporting member 56 is attached to the bottom 55 of the desk body 53 by any suitable means such as, for example, screws or bolts 61, FIG. 11.

The supporting member 56 also includes a leg portion 62 extending from the rear end of the leg 59 of the head 57. When the desk unit 56 is disposed in normal operative position, as shown in FIG. 8, the leg portion 62 of the supporting member 56 extends rearwardly and downwardly from the leg 59. The supporting member 56 also includes another leg 63 which, like the leg 58, forms a free end portion thereof, and the leg 63 is disposed substantially perpendicular to the leg 62, in substantially parallel relation to the leg 66 of the head 57, FIGS. 9 and 11.

The leg 63 is of such internal diameter that the rod 52 may be inserted longitudinally thereinto, and will fit therein with a relatively snug but freely slidable fit. ,It will be remembered that when the rod 52 is mounted in operative position in the chamber 28 of the combination desk and chair unit 51, it is disposed invdownwardly spaced relation to the lower face 13 of the seat 2 thereof, and the leg 63 of the supporting member 56 has a sufiiciently small outside diameter that the leg 63 may be slid longitudinally onto the free end portion 52a of the rod 52, which projects outwardly from the edge 17 of the panel member 12, when the rod 52 is mountedin operative position beneath the seat 2.

A substantially U-shaped supporting structure 64, which includes two spaced legs 65 and 66 at the opposite ends thereof and an intermediate portion 67 extending between the upper ends of the legs 65 and 66, forms the front support for the desk unit 50, FIG. 8. The leg structure 64 may be made of any suitable material such as, for example, steel tubing, and when it is disposed in operative position in the desk unit the intermediate portion 67 thereof is disposed in underlying relation to the front edge portion of the bottom of the desk body 53, forwardly of the leg portion of the supporting member 56. The intermediate portion 67 of the leg unit 64 is disposed in engagement with the leg portion 60 of the supporting member 56 and may be secured thereto by any suitable means such as, for example, welding.

The legs 65 and 66 of the leg unit 64 are so disposed relative to the intermediate portion 67 thereof that, when the leg unit 64 is attached to the supporting member 56 in the aforementioned manner, and the desk unit 50 is disposed in the operative position shown in FIG. 8, the legs 65 and 66 extend downwardly from the desk body 53 in position to support the front end thereof from the same fiat surface, such as, for example, a floor, that'the legs 3 and 4 of the combination desk and chair unit 51 rest upon.

The rod 52 has two tapped openings 68 and 69 formed in the end portion 52a thereof in spaced relation to each other longitudinally of the rod 52. The end portion 63 of the supporting member 56 also has two openings 70 and 71 formed therein. The openings 70 and 71 are so positioned in the leg 63 of the supporting member 56 that, when the leg 63 is disposed in normal operative position on the free end portion of the rod 52, the openings 7t} and 71 are aligned with the openings 68 and 69, respectively, in the rod 52. With the rod 52 and the leg 63 so positioned relative to each other, two bolts 72 and 73 may be inserted through the openings 70 and 71 and threaded into the openings 68 and 69 to thereby retain the leg 63 of the supporting member 56 against longitudinal movement relative to the rod 52. The bolt 72 has a head 74- thereon and when the desk unit 59 is disposed in normal operative position in the combination desk and chair unit 51 the bolt 72 may be screwed into the tapped opening 68 in position to clampingly engage the head 74 'with the outer peripheral surface of the end portion 63 of the supporting member 56 to thereby firmly hold the desk unit 50 against rotation on the rod 52.

As shown in the drawings, FIGS. 11, 12, 13 and 14, the opening 70 is a circular opening having a diameter just suflicient to permit the bolt 72 to be inserted there- 'through into the opening 68, but the opening 71 is an arcuate-shaped opening extending a substantial distance around the periphery of the leg 63. The opening 71 is disposed in such position on the leg 63 of the supporting member 56, and the legs 64 and 65 are so disposed relative to each other, that, when the bolt 72 is removed from the openings 68 and 70, the desk unit 50 of the combination desk and chair unit 51 may be rotated around the end portion 52a of the rod 52 in a counter-clockwise direction as viewed in FIG. 8, into the position shown in FIG. 11, wherein the desk 'body 53 underlies the seat 2, and the legs 65 and 66 project upwardly behind the back-rest 7 and laterally outwardly of the legs 3 and 4, respectively. In FIG. 11 the body portion 53 has been removed so as to more clearly show the underlying parts, but it will be appreciated that it is not necessary to remove the desk body 53 from the combination desk and chair unit 51 in order to move the desk unit 50 into or out of the folded position shown in FIG. 11.

Although in the preferred embodiment of the combination desk and chair unit 51, as shown in the drawings, the opening 70 is merely a circular opening which, when the desk unit 5t) is disposed in proper normal operative position relative to the seat 2, is axially aligned with the opening 68, and thus affords ready indexing of the proper position of the desk unit 50 relative to the seat 2, my invention is not limited thereto and the opening 70, if desired, may be arcuate in shape, like the opening 71 and,

7 with. this latter construction, it would not be necessary to remove the bolt 72 in order to move the desk unit 50 from the normal operative position shown'in FIG. 8 to the folded position shown in FIG. 1.1.

From the foregoing it will be seen that the present invention affords a novel and practical furniture construction wherein the seat of a chair unit may be supported in generally the same, novel and expeditious manner whether the chair comprises a unitary straight-back chair or a portion of a combination desk and chair unit.

Also, it will be seen that the present invention enables supporting structure to be connected to a seat in a novel and expeditious manner.

In addition, it will be seen that the present invention enables the supporting structure for seats to be produced by relatively simple manufacturing methods which readily lend themselves to mass production.

Also, it will be seen that the present invention affords novel furniture which is practical andeihcient in construction, and may be readily and economically produced commercially.

Thus, while I have illustrated and described the preferred embodiments of my invention, it is to be under stood that these are capable of variation and modification, and I therefore do not wish to be limited to the precise details set forth, but desire to avail myself of such changes and alterations as fall within the purview of the following claims.

I claim:

1. An article of furniture comprising a seat panel having a smooth lower surface, a panel member secured to said seat panel in engaging underlying relation to said surface, said panel member having a plurality of elongated, upwardly opening concavities therein to thereby afford elongated chambers between said panel member and said seat panel with said seat panel aifording the top wall of said chambers, and elongated supporting means mounted in said chambers and projecting downwardly therefrom in position to support said seat panel.

2. An article of furniture as defined in claim 1 and in which two of said chambers are disposed in parallel relation to each other and are open at one end at one edge of said panel member, and another of said chambers is disposed perpendicular to said two chambers in spaced relation thereto and opens at its opposite ends at opposite side edges of said panel member, and in which said supporting means comprises a leg means disposed in and projecting outwardly from each of said open ends of said three chambers.

3. An article of furniture as defined in claim 1 and in which two of said chambers are disposed in parallel relation to each other and are open at one end at one edge of said panel member, and another of said chambers is disposedperpendicular to said two chambers in spaced relation thereto and opens at its opposite ends at opposite 4. An article of furniture as defined in claim 1, and in 6 which said supporting means comprises leg means projecting from one side of said body portion, and desk means disposed on the other side of said body portion from said leg means, said desk means comprising another panel member having a front edge, a rear edge and two oppositely disposed side edges, said panel member being mountedon said seat panel in underlying engagement therewith and having a plurality of upwardly-opening elongated concavities therein to afiord a plurality of elongated chambers between said seat panel and said panel member with said seat panel aifording the top wall of said chambers, certain of said chambers extending generally forwardly and rearwardly and being disposed in substantially parallel relation to each other in the rear edge portion of said panel member and opening outwardly between said seat panel and said rear edge, another of said chambers being disposed in the front edge portion of said panel member and extending substantially perpendicular to said forwardly and rearwardly extending chambers,

said other chamber opening outwardly between said two.

side edges and said seat panel, said panel member having a plurality of downwardly projecting ribs disposed be 1 tween said other chamber and the remainder of said chambers, and supporting means mounted in all of said chambers in engagement with said seat panel and said panel member and projecting outwardly from said seat? panel.

6. An article of furniture as defined in claim 5, and in which said supporting means includes elongated legs welded to said panel member.

7. An article of furniture as defined in claim 5, and

which includes a back-rest panel disposed above said seat panel, and in which said supporting means mounted in said forwardly and reaiwardlyextending chambers include elongated members having one end disposed in certain of said last mentioned chambers and another end secured to said back-rest panel in supporting relation to the latter.

8. An article of furniture as defined in claim 5, and in p which said supporting means mounted in said other cham- J ber includes :a desk unit disposed in forwardly projecting relation to said seat panel.

References Cited in thefile of this patent UNITED STATES PATENTS D. 170,005 Chapman July 14, 1953 D. 188,241 Christenson' June 21, 1960 552,502 Andrews Jan. 7,; 1896' 2,210,047 Stieglitz 'Aug. 6, 1940 2,459,257 Wood Jan. 18, 1949 2,569,729 Nold Oct. 2, 1951 2,815,067 Richardson Dec. 3, 1957 r 2,815,801 Fingerhut Dec. 10, 2,970,635 Fields Feb. 7,1961

' FOREIGN PATENTS 550,588 Italy Nov. 3', 1956 OTHER REFERENCES Arlington 400 line pamphlet, received in Office Feb. 2, 1957, 410 Study desk item XD33-11. 

5. AN ARTICLE OF FURNITURE COMPRISING A SEAT PANEL, A PANEL MEMBER HAVING A FRONT EDGE, A REAR EDGE AND TWO OPPOSITELY DISPOSED SIDE EDGES, SAID PANEL MEMBER BEING MOUNTED ON SAID SEAT PANEL IN UNDERLYING ENGAGEMENT THEREWITH AND HAVING A PLURALITY OF UPWARDLY-OPENING ELONGATED CONCAVITIES THEREIN TO AFFORD A PLURALITY OF ELONGATED CHAMBERS BETWEEN SAID SEAT PANEL AND SAID PANEL MEMBER WITH SAID SEAT PANEL AFFORDING THE TOP WALL OF SAID CHAMBERS, CERTIAN OF SAID CHAMBERS EXTENDING GENERALLY FORWARDLY AND REARWARDLY AND BEING DISPOSED IN SUBSTANTIALLY PARALLEL RELATION TO EACH OTHER IN THE REAR EDGE PORTION OF SAID PANEL MEMBER AND OPENING OUTWARDLY BETWEEN SAID SEAT PANEL AND SAID REAR EDGE, ANOTHER OF SAID CHAMBERS BEING DISPOSED IN THE FRONT EDGE PORTION OF SAID PANEL MEMBER AND EXTENDING SUBSTANTIALLY PERPENDICULAR TO SAID FORWARDLY AND REARWARDLY EXTENDING CHAMBERS, SAID OTHER CHAMBER OPENING OUTWARDLY BETWEEN SAID TWO SIDE EDGES AND SAID SEAT PANEL, SAID PANEL MEMBER HAVING A PLURALITY OF DOWNWARDLY PROJECTING RIBS DISPOSED BETWEEN SAID OTHER CHAMBER AND THE REMAINDER OF SAID CHAMBERS, AND SUPPORTING MEANS MOUNTED IN ALL OF SAID CHAMBERS IN ENGAGEMENT WITH SAID SEAT PANEL AND SAID PANEL MEMBER AND PROJECTING OUTWARDLY FROM SAID SEAT PANEL. 